Method of cutting a skin graft



June 1, 1948. J. D. REESE METHOD OF CUTTING A SKIN GRAFT Filed July 31,1945 INVENTOR.

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Patented June 1, 1948 UNITED STATES PATENT OFFICE METHOD OF CUTTING ASKIN GRAFT John D. Reese, Philadelphia, Pa.

Application July 31, 1945, Serial No. 607,988

Claims. 1

This invention relates to skin grafting, more particularly to thecutting of skin grafts from donor areas, and has fOr an object toprovide an improved method of cutting such grafts.

In using dermatomes of the so called drum type, comprising a body memberhaving a convex outer surface adapted to be coated with an adhesive fortemporary retention of a skin graft thereon, together with askin-cutting blade mounted for rotation and reciprocation relative tothe convex surface for separating the skin graft from the body of thepatient while the adhesive convex surface is rolled or rocked on thelatter, as fully disclosed in United States Letters Patent No.2,288,709, granted July '7, 1942, to G. J. Hood and in applicants priorPatent No. 2,366,054, granted December 26, 1944, it is standard practiceto coat the convex skin-engaging surface of the dermatome with asuitable adhesive, for example, a rubber cement, and likewise to coatthe donor area of the patient with the same type of adhesive.

Under this prior practice, when the convex surface of the dermatome isrolled or rocked on the donor area, the two coats of adhesive cohere toeach other and become, in effect, a single layer of adhesive connectingthe dermatome surface and the donor area skin. The rolling action of thedermatome on the patients body pulls upwardly on the skin and lifts itaway from the body, this lifting force tending to cause failure of theadhesion between the layer of adhesive and the skin, or between thelayer of adhesive and the metallic surface of the-dermatome.

Obviously, any such failure of the adhesive connection between the donorarea skin and the dermatome results in the cutting of holes in the graftof areas corresponding to the areas over which the adhesive fails.

The frequent failure "of the adhesive used by the profession in thecutting of skin grafts in the manner explained above appears to resultfrom the fact that the adhesive is of such character that if it adheressuitably to the convex metallic surface of the dermatome, then it doesnot adhere suitably to the human skin, and conversely, if the adhesiveis such that it adheres properly to the human skin, it lacks the abilityto adhere properly to the metal surface of the dermatome.

Since the drum type of dermatome came on the market several years ago,the profession has cifically, the adhesive applied to the dermatomeconvex surface would be one selected for its high cohesiveness ofadhesion for the particular material of which the dermatome convexsurface is made (usually brass) while the adhesive applied to the donorarea skin would be one selected for its high cohesiveness of adhesionfor human skin.

Regardless of the types of adhesives selected, the two differentadhesives will cohere to each other, when the dermatome is rolled on thedonor area, more securely than either adhesive will adhere to theparticular surface to which it is applied. Thus, the use of the proposedcombination of two different adhesives assures of the least possibilityof failure of the connection between the demnatome and the donor areaskin during cutting of the graft.

Furthermore, it is proposed that the selection of the two adhesives takeinto consideration the relative cohesiveness of adhesion of the firstadhesive to the dermatome surface and of the second adhesive to thedonor area skin, it being desirable that the first adhesive adhere moresecurely to the dermatome than the second adhesive adheres to the graft,so that when the cutting of the graft has been completed, and it isdesired to pull the graft from the dermatome convex surface, theadhesion between the skin graft and the adjacent coating of the secondadhesive will fail, permitting removal of the skin graft free of alladhesive matter.

Therefore, another object of the invention is to provide, for use in thecutting of skin grafts, a novel method of temporarily retaining thegraft on the dermatome.

A further object of the invention is to provide a method of cutting askin graft, which method will assure separation of the cut graft fromthe dermatome free of all adhesive material used in cutting the graft.

These and other objects are effected by the invention as will beapparent from the following description and claims, taken in accordancewith the accompanying drawing, forming a part of this application, inwhich:

Fig. 1 is a front elevational view, partiall in section, of a dermatomefor use in performing the method of the present invention;

Fig. 2 is a vertical sectional view, taken along the line II-II of Fig.1, looking in the direction indicated by the arrows, portions of thestructure being broken away for the sake of clearness;

Fig. 3 is a vertical sectional View, taken along the line III-III ofFig. 1, looking in the direction indicated by the arrows; and

Fig. 4 is an enlarged, fragmentary view of a portion of the structureshown in Fig. 3.

Referring now to the drawing more in detail, the dermatome, indicated inits entirety by the reference character l0, comprises a drum or bodyportion l I of semi-cylindrical form, having a pair of spaced side wallsI2 and I3, joined alon their curved edges by a concave-convex wall l4,

constituting a skin-engaging 01' graft-receiving face.

A shaft I6 is 'journalcd in a bearing ll'extend ing between, andsupported by, the side walls l2 ciding with the axis of generation ofthe convex surface [8 of the wall I4.

A pair of posts 28 and 2! are supported in par allel spaced-apartrelation on the terminal portions of the shaft l6, and carryattheirfree'outer r107 ends 22 and 23, respectively, a knife-holdingbar- 24, on which is supported a graft-cutting blade or knife 25,Inasmuch as the space. between the posts 20"and 25 is materiallygreater.than'th'e'i width'of the drum or bod ymember' I l; therectangle formedby the" shaft is, the posts'20 and 2f," 'andthe knife-holding bar 24L-and knife 25' may be reciprocated and rotated as a unit rela t tive tothe body member I l. During such move ment; the cutting edge of theknifewill'always. be parallel to the convex surface IB'and at a predetermineddistance, therefrom, du'e'to the axis of the shaft'lS coinciding withthe axis'of generation of the convex surface l8;

It' is believed unnecessarytoLdescribe in' this application, furtherdetails of construction of'the dermatome l6, as sufficient structure hasalready? been explained to enablefithc'selskilled in the art I tounderstand and appreciate'thenovel features of thepresentinvention, nowto be described. -If a more. detailed description of the dermato'me-lflis desired,-reference may be had to applicants prior Patent No,2,366,054; granted December 26," 1944. V

In' accordance with the preseht'inventionfthe convex surface l8'of thedermatome l0 iscoated i with an adhesive A (Fig; 4), which adhesive'hasi a high coefiicient ofladhesion for the articular materialof whichthe concave-conVex-wall 14' is made.- Usually thismaterialis brass, "anda rubber basecement, for example, running board cement, may be foundsatisfactory, Runningboard cement-consists of vulcanized rubberdissolved in acids,

Similarly, a coating, of adhesive 7 B is applied to the patients donorarea skin S, this second adhesive B having a high coefficient ofadhesion for human skin; A 'rubber'base cement, for. example,l artistscement, Jmay be" employed "with satisfactory results. Artists cementconsists of raw rubber dissolved in napth'as.

Preferably, twodifferent adhesives A "andrB are. selected. which willresult in' the adhesive A adheringdtighte'r. to the dermatomesurfacefilB than the adhesive B 'adheresto'the skin Sywith. ,55 theresult that when it is sought'toremove' the: cut graft G fromrthedermatome to' which-it is secured by the coherin'g' coatings of adhesiveA and Bfand force is applied to the graftG to pull. it-away fromthe'dermatome surface [8, the adhesion. between. theadhsive B and-thegraft G will fail first -thereby permitting removal of the graft JG freeof the coating of adhesive B previouslyapplied thereto, the, coating. ofadhesive '3 cohering .to the. coating of adhesive A andvthe latteradhering to the. dermatome.

It maybe. desirable to add coloring matter to the adhesives if they donot'naturally'possess a color clearly distinguishing ,them from the.surfacetoswhich they are to be applied; in order that the .user maybesure that the coatings of adhesives" completely cover'the desiredareasof the dermatome convex'surface l3 and of the donor area'skin'S.-

While the'invention-ha's been illustrated in '7 4 but one form, it willbe obvious to those skilled in the art that it is not so-limited but issusceptible'of various modifications and changes, as well as otherapplications, without departing from and I 3, the longitudinal axis ofthe shaft [6 coin-r 5 thesp i t f- What is claimed is:

1. In' a method of cutting a skin graft with a dermatome having a convexskin-engaging surface, the'steps of coating the convex surface with Iafirstzadhesive', and coating 9. section of donor area skin with a secondadhesive which will adheretighter to the first adhesive than to the skinand will adhere to the skin less tightly than the first adhesive adheresto the dermatome' convex surface.

2. In a method of cutting a skid-graft witna 1' 'dermatome having aconvex skin-engaging'=sur'-. face, the steps of'coating said:derm'atomeconvex surface with -a first adhesivewhichadheres tightlythereto;--and coating-a sectionnof-donor f area skin withfiasecondadhesive-which adheres: less tightly tothe skin than thefirstedheslve does to the dermatome and than the secondad hesive does tothe firstadhesive:

3. In a method ef-cuttinga skin-graftwitlra 1 dermatome having a convexskin-engaging metallic surface, the steps of coating said "convex' imetallic surface with a metal-adhesive cement; and coating a sectionof-dono'r-area skinwith a human skin-adhesive cement whose coeflicientrfof adhesion for the donor area skin i's lesslth'ani the coefficient ofadhesion of the" metal adhesive cement forthe" metallic "convex surfac'eof -the dermatorne.-'

4. In a method of cutting a skin'graft witna dermatome'havinga metallicskin-engaging surface, the steps of coating said metallic surface with-a metal-adhesive "material, -and: coating a donor I areaof skin with 'ahuman skim-adhesive i material which adheres to the donor area-skin iless firmly than it doesto 'the metal-adhesive material, and lessfir'mlythan the lattcr adhercs to the dermatoine metalllc surface.1

5. In a method of cutting a skin graftwvith -a dermato'me having a"convex skin engaging sur-v face, the steps of coating saidconvex'surface with a first rubber-cement'having -a high coeificient ofadhesionfor-the material of Which'fsaidsurface is compcsed,'and=coatinga donor area of' skin with a second rubbencement having-alower coefiicient of adhesionfor human skin-"than the first rubbercement has forthe material of which the dermatome convex surface iscomposed, whereby, when the two rubb'er cements have been caused tocohere 'together by'rocking the coated i convex surface on the "coateddonor area skin; and a graftsimultaneouslybut from said donorarea andleft adhering to the dermatome convex surface by thetwo cohe'ringcements, pulling of the graft'from-the dermatome will beefi'e'ctedbyfailure of the adhesion'between the graft'and the second rubbercement, rather than: by failure of the adhesion-between'the first rubbercement and the dermatome'. or-by failure of the cohesion -between thetwo cement-s;

JOHN D. REESE;

REFERENCES CITED UNITED STATES PATENTS Name Date Hood July 7,1942

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